Electrically operated paintball gun having hammer and bolt mechanism

ABSTRACT

An electrically operated paintball gun operable to fire paintballs including a barrel, a trigger, and a breech connected to a rear end of the barrel, as well as a bolt movable in the breech between a rearward position and a forward shooting position. A hammer is connected to the bolt and movable therewith and is slidable in a sealable chamber between a rearward position and a front shooting position. A spring biases the combination of the bolt and hammer towards the rearward position of each. A pneumatic circuit is provided to drive the hammer towards the front position and includes a control valve in the form of a solenoid valve to receive gas under pressure and direct it into the chamber at the rear of the hammer when the gun is shot. An electronic circuit controls the pneumatic circuit and is operated by an electrical switch operated by the trigger. A gas valve is opened by engagement by the hammer, when the latter is driven forwardly to the shooting position, to permit the passage of relatively high pressure propellant gas into the barrel to propel a paintball.

BACKGROUND OF THE INVENTION

[0001] This invention relates to guns capable of firing paintballs by using pressurized gas and in particular to such guns that are electronically operated.

[0002] Guns capable of firing paintballs by use of pressurized gas have been known for a number of years and they are commonly used for recreational sports such as survival or “war” games. The paintballs fired by these guns generally comprise a gelatin shell with a colored liquid or viscous substance in the interior. These paintballs are designed to burst upon impact with a target and thereby create a very visible mark on the target.

[0003] Up until recently the firing mechanisms in paintball guns have generally been mechanical in nature and have not been electrically operated. An example of such a gun is that disclosed in and illustrated in U.S. Pat. No. 5,349,939 issued Sep. 27, 1994 to Brass Eagle Inc. This gun has a hammer mechanism slidably mounted in the breech. A spring is used to drive the hammer forwards when the gun is fired. A sear device having a front and a rear end is mounted on a sear pin in the breech. A sear spring biases the sear device so that the front end thereof pivots downwardly after the hammer is released. A sear detent is slidably mounted in a front end of the sear device and a small spring biases this detent to move to a forward position in order to be engageable by the trigger.

[0004] Recently, electronically operated paintball guns have come into use and have become popular. One such paintball gun is described in recent U.S. Pat. No. 5,881,707 issued Mar. 16, 1999 to Smart Parts, Inc. The grip of the gun has an electrical switch capable of activating a launching sequence. An electrical control unit is housed within the body of the gun and a grip and can direct pressurized gas flow between the pneumatic components of the gun in order to load, cock and fire the gun. The electrical control unit includes an electrical power source which activates an electrical timing circuit when the electrical switch is closed, and two electrically operated pneumatic flow distribution devices. Upon closure of the switch, the control unit causes a projectile to be loaded into the launching mechanism by actuation of the first pneumatic flow distribution device. A paintball is fired when the timing circuit actuates the second flow distribution device to release gas from a storage chamber into the launching mechanism.

[0005] Another electronically activated gun is that described in U.S. Pat. No. 6,003,504 issued to NPF Limited on Dec. 21, 1999. This gun employs first and second gas pressure regulators with the first capable of providing high gas pressure in a first chamber of the gun. The second regulator is connected between this first chamber and a second chamber and maintains a lower working pressure in the second chamber. A control valve receives gas under pressure from the second chamber and directs it selectively to a ram slidably mounted in a cylinder. The ram is moved by gas pressure between a retracted position and a forward position where it opens a valve to allow high pressure gas to flow from the first chamber to the barrel to fire a paintball. The gun's trigger operates a microswitch which is part of an electronic control circuit for the gun.

[0006] It is an object of the present invention to provide a relatively simple, low cost, electronically operated paintball gun that employs a pneumatic circuit for driving the hammer and the bolt towards a front shooting position and a spring to bias the hammer and bolt combination to a rearward position after the gun is shot.

[0007] It is also an object of the present invention to provide a novel paintball gun that employs an electronic circuit for controlling a pneumatic circuit of the gun and that can be manufactured easily and at reasonable cost.

SUMMARY OF THE INVENTION

[0008] According to one aspect of the present invention, a paintball gun operable to shoot paintballs includes a barrel, a gun body section including a breech connected to a rear end of the barrel and a handle section, and a trigger movably mounted on said gun body section. A bolt is movable in the breech between a rearward position where a paintball can enter the breech section through an inlet and a front shooting position where the inlet is closed. A hammer is connected to the bolt and movable therewith and the hammer is slidable in a sealable chamber in the gun body section between a rearward position and its front shooting position. A spring is mounted in the gun body section and engages the hammer and bolt combination and thereby biases both the bolt and the hammer towards their respective rearward positions. A pneumatic circuit is used to drive the hammer and the bolt towards the front shooting position and includes a control valve arranged to receive gas under pressure and direct the gas (when the gun is shot) to a rear side of the hammer. An electronic circuit controls the pneumatic circuit and includes an electrical switch operated by movement of the trigger. The gun further includes a gas valve mounted therein and adapted to be opened by engagement by the hammer in the front firing position to permit passage of pressurized gas from a pressurized gas source to the barrel to propel a paintball along and out of the barrel.

[0009] The preferred gun includes a battery connected to the electronic circuit which includes an on/off switch. The preferred electronic circuit includes a mircocomputer with a timer capable of controlling the length of time when the control valve directs gas under pressure to the rear of the hammer.

[0010] According to another aspect of the invention, there is provided in a gas powered gun for firing balls, a barrel, a gun body section including a breech behind the barrel for receiving one ball at a time through a ball feed port, a trigger movably mounted in the gun body section, and a bolt slidable within the breech to advance a ball to a shooting position and close off the feed port. This gun also has a regulator for supplying pressurized gas at a relatively low gas pressure, this regulator being adapted for connection to a source of relatively high-pressure gas. The improvements in this gun include a hammer rigidly connected to the bolt and movable therewith, this hammer being slidable in a sealable chamber formed in the gun body section between a rearward position and a front shooting position. Thus the bolt and hammer together form a ball shooting mechanism. There are means for biasing the shooting mechanism so as to move the hammer towards the rearward position. A solenoid valve having an inlet connected to the regulator is arranged to deliver relatively low pressure gas to a rear side of the hammer for moving the ball shooting mechanism forwardly to the shooting position when the solenoid valve is in the open position. The improvements further include an electronic circuit for controlling the solenoid valve, this circuit including an electrical switch operated by the trigger, and a valve mechanism for permitting the relatively high pressure gas to flow into the barrel in order to propel a ball along and out of the barrel, this valve mechanism being moved to an open position by engagement of the hammer in the front shooting position.

[0011] In a preferred embodiment, the biasing mechanism is a coil spring mounted in the breech and engaging the bolt at one end of the spring. The preferred electronic circuit is powered by a battery connected thereto and this circuit her includes a manual ON/OFF switch, and an electronic switch which is capable of shutting down the electronic circuit automatically in order to save battery power.

[0012] According to still another aspect of the invention, a paintball gun operable to fire paintballs comprises a barrel, and a gun body section attached to the barrel and including a breech section co-axial with the barrel and a movable trigger. The gun further includes a bolt mounted in the breech section and movable between a retracted position for paintball loading and a forward position for shooting a paintball and a hammer rigidly connected to the bolt and movable therewith. The hammer is in a sealable chamber in the gun body section between a retracted position and a forward position. The gun includes spring means for moving the combination of the bolt and the hammer to the retracted position after a paintball is shot and a first pneumatic circuit for delivering propellant gas at a relatively high pressure from a supply to the barrel for propelling the paintball therefrom. This first pneumatic circuit includes a relatively high pressure gas valve. There is also a second pneumatic circuit connected to receive pressurized gas from the gas supply, this circuit including a solenoid valve for delivering relatively low pressure gas to a rear end of the hammer for a short time interval in order to drive the combination of the hammer and the bolt from their retracted positions to their respective forward positions and thereby cause the hammer to strike the gas valve to open it and release the propellant gas into the barrel. An electronic circuit is also provided to operate the solenoid valve and this circuit is operable by the trigger.

[0013] Preferably the spring mechanism of this gun is a coil spring mounted in the breech section and engaging the bolt at one end of the coil spring.

[0014] Further features and advantages of the paintball gun of this invention will become apparent for the following detailed description taken in conjunction with the accompanying drawings which illustrate preferred embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a side elevation of a first embodiment of a paintball gun constructed in accordance with the invention with portions of the gun shown in cross section for purposes of illustration, the gun being shown in the shooting position;

[0016]FIG. 2 is a side elevation similar to FIG. 1, again with portions shown in cross section, this view showing the first embodiment in a loading position with both the bolt and the hammer retracted;

[0017]FIG. 3 is a side elevation similar to FIG. 1 but on a larger scale, the gun being shown in the shooting position with portions of the gun cut away for purposes of illustration;

[0018]FIG. 4 is a side elevation, substantial portions of which are in cross-section, illustrating a second embodiment of a paintball gun;

[0019]FIG. 5 is a top view of an upper body section of the gun of FIG. 5;

[0020]FIG. 6 is a longitudinal cross-section of the upper gun body section taken along the line VI-VI of FIG. 5;

[0021]FIG. 7 is a bottom view of the upper body section of FIGS. 5 and 6;

[0022]FIG. 8 is a front end view of the upper body section of the gun;

[0023]FIG. 9 is a top view of a lower section of the gun body;

[0024]FIG. 10 is a longitudinal cross-section of the lower section, this view being taken along the line X-X of FIG. 9;

[0025]FIG. 11 is a front view of the lower body section of FIG. 10; and

[0026]FIG. 12 is a circuit diagram for a preferred electronic circuit to operate the gun of the invention; and

[0027]FIG. 13 is a top end view of an upward extension of a regulator used in the second embodiment.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0028] A first embodiment of a paintball gun 10 constructed in accordance with the invention is shown in FIGS. 1 and 2 and on a larger scale in FIG. 3. It will be understood that this gun employs a standard CO₂ cylinder (not shown) which is attached by means of a standard connector housing 12 which can be connected to a bottom end of a gun grip 14. The housing 12 can be internally threaded at one end 16 where the CO₂ cylinder can be attached by the threads. Attached to the front end of a housing 12 is a short length of flexible metal CO₂ hose 18 capable of carrying relatively high pressure gas, typically in the range of 750 psi. A standard brass fitting (not illustrated) can be used at each end of the hose 18 to connect same to the housing 12 and to a downward extension 20 of a gun firing CO₂ valve.

[0029] The gun 10 is adapted to fire paint pellets or paintballs 24, one of which is shown in FIG. 1 in a paintball feed tube 26, only a portion of which is shown. These paintballs are of well known construction and of standard size and they will readily break upon impact with a target. The gun 10 includes a barrel 28 which can vary in length and, as illustrated in FIGS. 1 and 2, a portion of the barrel has been cut away at 30. Rigidly connected to the rear end of the barrel is a breech 32. The illustrated gun has a sight protector 34 of standard construction on top of the breech. Slidably mounted inside of the breech is a bolt 36 which can be generally cylindrical. The bolt is movable between a retracted position shown in FIG. 2 where a paintball 24 can enter the breech 32 through an inlet 40 formed in the top of the breech and a front firing or shooting position shown in FIGS. 1 and 3 where the inlet is closed.

[0030] An elongate metal hammer 42 is connected to the bolt 36 by means of a metal pin 44 extending between them. The pin 44 which can be made of steel is preferably force fitted into a hole 46 formed in the bottom of the bolt. The bottom portion of the pin extends through elongate slot 48 and into a cylindrical hole 50 formed in a forward end of the hammer 42. It will be understood that the hammer moves in an elongate chamber formed in a gun frame 52 of which the grip 14 can be integral component. This gun frame or gun body section can either be made of a suitable metal or a strong, rigid plastics material such as fiberglass filled nylon.

[0031] Pivotably mounted in this gun frame is a pivotable trigger 54 which can be protected by trigger guard 56. Rearward movement of the trigger operates a standard microswitch 58, the casing of which is rigidly mounted in the gun frame. In a known manner, the trigger can operate a small button on the front of the microswitch, the pressing of this button causing the electronic circuit to which the microswitch is connected to commence a launching sequence in order to fire one or more paintballs using compressed gas. The trigger 54 can be spring biased towards its forward position in several possible ways. Firstly it can be spring biased by a spring biased button on the microswitch itself or it can be biased by a separate torsion or compression spring that acts on the trigger and is mounted in the gun frame or gun body section 52. In the case of a torsion spring, it can be mounted on the pivot pin for the trigger. Such springs for biasing a trigger are well known in the paintball gun art and accordingly it is deemed unnecessary to illustrate or describe in detail such a spring.

[0032] A threaded metal CO₂ hose connector 65 is detachably connected to the rear end of the gun frame and closes off the rear end of a sealable chamber 66 of the gun body section in which the hammer slides. A relatively long, metal CO₂ hose 68 shown in FIGS. 1 and 2 is connected to the connector 65 at one end and delivers pressurized gas having a relatively low gas pressure through the connector and its passageway 70 into the chamber 66 from a solenoid valve 72. It will be understood that this pressurized gas having a relatively low gas pressure is employed in the gun in order to move the hammer (and the attached bolt) rapidly forwardly in order to open the two way gas valve 76 by striking a valve pin and thereby release relatively high pressure gas into the barrel through the interior of the bolt. The bolt has a high pressure gas passageway 78 in a forward section thereof and the front of this passageway opens into the barrel when the bolt has been advanced to its forward position. It will be understood that the gas valve 76 is of standard construction for a paintball gun and accordingly a detailed description herein is deemed unnecessary. It will be understood that relatively high pressure gas, i.e. 750 psi is provided to the inlet of this valve through its downward extension 20 and the hose 18.

[0033] In this first embodiment, there is mounted beneath the barrel 28 and in a forward portion of the gun a gas regulator 80 of standard construction. This regulator receives the relatively high pressure gas from the valve 76 and provides pressurized gas at a substantially lower pressure to the solenoid valve 72 which is controlled by the electronic circuit of the gun. The solenoid valve can be a standard two way valve having an open position in which the lower pressure gas flows through the hose 68 in order to drive the hammer forwardly and a closed position that terminates the flow of this gas through the hose. The length of time in which the valve 72 remains in the open position is precisely controlled by the programmable logic circuit (PLC) or microcomputer of the gun. This circuit can be constructed to fire the gun not only once but two or three or more times with a single pull of the trigger, if desired. The number of paintballs fired in a single burst can be set by the user, for example, by a setting established with small buttons or pins or a single button or pin mounted in the side of the gun (see the circuit description below).

[0034] The electronic circuit board, which includes the PLC or microcomputer can be mounted in the grip 14 and is indicated by the dashed rectangle at 83 in FIG. 3. A detailed description of one version of the electronic circuit board is provided below. It will be understood that the length of time that the lower pressure gas is delivered through the passageway 70 and into the chamber 66 is dictated by the PLC or microcomputer which controls the operation of the valve 72 through which this gas flows.

[0035] In the paintball gun of FIGS. 1 to 3, a spring 85 is mounted in the gun and engages the hammer 42 so as to bias the hammer towards its rearward position which is shown in FIG. 2. The preferred spring is a coil spring that extends about the circumferential periphery of the hammer. The rear end of the spring engages a shoulder 86 formed near the rear of the hammer. The forward end of the spring engages a rearwardly facing shoulder 88 formed in the wall of the cylindrical chamber containing the hammer. Also provided near the rear end of the hammer is an O ring seal 90 which fits into a circumferential groove in the hammer. In order to seal the rear end of the chamber 66, an O ring seal 92 is also provided about the circumference of the hose connector 65.

[0036] Once the hammer and the bolt have advanced to the front firing position, the pressurized gas to the rear of the hammer must be released from the chamber 66. This can be accomplished by a suitable air outlet passageway formed in the gun body and which can be located at 94. The outlet 94 is located in the wall of the chamber just to the rear of the hammer when the hammer is advanced to the front firing position. The pressure created by any remaining air in the chamber is readily overcome by the force of the coil spring 85 in order to return the hammer to the retracted position. A battery, such as a 9 volt battery can be mounted at any one of several possible different locations in the body of a gun, this battery being connected to the electronic circuit board 83. A 9 volt battery mounted in the grip 14 is illustrated in dash lines at 96 in FIG. 3. A simple, electrical on-off switch (not shown) is also mounted on the side of the gun at a convenient location in order to turn the electrical control circuit on for use of the gun.

[0037] Instead of using the external gas hoses 18 and 68, it will be appreciated by those skilled in the paintball gun art that internal gas passageways can readily be formed in the gun housing and in the grip 14 to allow the passage of pressurized gas between the required points. By providing internal gas passageways in the gun to replace one or both of the hoses, one will avoid or lessen the possibility of a hose interfering with the use of the gun.

[0038] Generally the paintball gun of FIGS. 1 to 3 will also be provided with a safety mechanism to help prevent accidental firing of the gun. This safety mechanism can be any of the well known types of safeties including a safety switch to block movement of the trigger 54.

[0039] One possible construction for the low pressure gas regulator 80 is that of the low pressure regulator illustrated and described in U.S. Pat. No. 5,878,736 which issued Mar. 9, 1999. This low pressure regulator has a hollow piston, a coil spring and a seal all contained within a housing. The disclosure and drawings of this U.S. patent in connection with the low pressure regulator are incorporated herein by reference. This known regulator is capable of providing constant lower pressure gas at its outlet port in the range of 80 to 150 psi.

[0040] A second version of the paintball gun constructed in accordance with the invention is illustrated in FIG. 4 of the drawings. This second version indicated generally by reference 100 is similar in its construction to the paintball gun 10 illustrated in FIGS. 1 to 3, except as described differently in the following description. This paintball gun also has a gun grip or handle 14 and an elongate barrel 28 which can vary in length. Rigidly connected to the rear end of the barrel is a gun body section identified generally at 102 and this gun body section includes a breech section 32. In a preferred version of this paintball gun, the gun body section comprises two principal body parts, these being an upper body section 104 illustrated in FIGS. 5 to 8 and a lower body section 106 illustrated in FIGS. 9 to 11. The lower body section includes the handle section or grip 14.

[0041] Mounted on the upper body section 104 is a paintball feed tube 26 which opens into a circular hole 108 in the top of the body section 104. Extending along the top of the body section 104 is a longitudinal ridge 110 which forms a V-shaped sight. Extending through the body section 104 is a straight, longitudinal upper passage 112 and formed in the bottom thereof is a lower chamber 114. Slidably mounted in the upper passage 112 is a bolt 116 which is movable in this passage between a retracted position as shown in FIG. 4 where a paintball can enter the breech section through the inlet or opening 108 and a front firing position where the inlet 108 is closed. It will be understood that this front shooting position would be similar to that shown in FIG. 1. Rigidly connected to the bolt is the elongate metal hammer 42 with the metal pin 44 connecting the bolt to the hammer in the manner explained above. The pin 44 extends through a longitudinal slot 48 formed between the passage 112 and the chamber 114. It will be understood that the rear portion of the chamber 114 forms a sealable chamber when the hammer is mounted in the chamber 114. This is due in part to the presence of the O-ring seal 90 which extends around a circumferential groove near the rear end of the hammer. There is also a further O-ring 118 mounted in a circumferential groove formed on a rear plug member 120. This plug member is held in place by an upper screw 122 that extends through a hole formed in the rear end of body section 104. Extending through the plug member 120 is L-shaped passage 126 that opens into the chamber 114 at the rear of the hammer. Also formed in this plug member is a recess 130 which receives the head of a screw 132 threaded into the rear end of the bolt.

[0042] The bolt 116 is also fitted with two O-ring seals 131, 133 mounted in circumferential grooves in the bolt. These two seals act at seal the section of the bolt where the propellant gas enters when the gun is shot.

[0043] Referring now to the details of the upper body section shown in FIGS. 5 to 8, this section is formed with a hole for the passage of high pressure gas at 136. There is also a small screw hole 138 formed in the bottom of its rear end to receive a connecting screw 140 used to connect the lower body section 106 to the upper body section.

[0044] Located a short distance forwardly of the hole 138 is a larger hole 142 through which relatively low pressure gas passes into the aforementioned passage 126. Also located in the bottom of this member is a circular hole 144 which can be used in the assembly of this gun (ie. permitting the insertion of the pin 44 through the front end of the hammer and into the bolt). Extending downwardly from the body section 104 are two spaced apart tabs or brackets 146. These are used to connect the body section 104 to the front end of the lower body section 106 by means of a screw or bolt (not shown).

[0045] Turning now to the lower body section illustrated in FIGS. 9 to 11, the lower body section forms a cavity 150 in which is mounted a solenoid valve 152 shown in FIG. 4. Projecting into the interior of this cavity are two connectors 153 that form screw holes for mounting an electronic circuit board 154 shown in FIG. 4. Two mounting screws 156 are used for this purpose. Formed in the bottom of the body section 106 are front and rear screw holes 158, 159. By means of three screws (not shown) extending through these holes, there is mounted at the bottom end of the cavity 150 a gas pressure regulator 160. This regulator is formed with an upwardly projecting extension 162 through which extend passageways for pressurized gas. The regulator 160 can be similar to the low pressure gas regulator 80 of the first version of the gun, except that this regulator is adapted for mounting at the bottom end of the handle. A preferred version of this regulator provides relatively low pressure gas at its outlet having an adjustable pressure ranging between 80 and 120 psi.

[0046] It will be understood that plastic or wooden handle grips (not shown) can be attached to both sides of the illustrated lower body section 106. These hand grips can be detachably connected to the frame or body section by means of two screws on each side that are threaded into screw holes 260, 261.

[0047] Returning to the body section 106, this section has a rear end hole 164 for the passage of the aforementioned screw 140 and there is a short rear wall 166. Located above the trigger guard 56 are two small holes 168 which are used to support a trigger pin 170. The two holes 168 are formed in short upper sidewalls 172, 174 which extend from the front end of the body section to the rear wall 166. Formed in the front end of these sidewalls are two aligned connecting holes 176. It will be understood that a screw extends through these holes and through the aforementioned tabs 146 to connect the two body sections at this location. There is also a connecting screw hole formed at 180.

[0048] The preferred paintball gun of FIG. 4 has a bolt and hammer combination which can be termed a ball shooting mechanism and there are means for biasing this shooting mechanism so as to move the hammer 42 to its rearward position, that is the position shown in FIG. 4. In this gun, the preferred biasing means is a spring 184 mounted in the breech section. For this purpose, it will be seen from FIGS. 4 and 6 that the passageway 112 is formed with a larger internal diameter at a rear portion thereof so as to accommodate the spring. Thus, the front end of the spring bears against an internal shoulder 186 while a rear end of the spring bears against a shoulder formed near-the rear end of the bolt. The preferred spring 184 is a coil spring that extends about the circumference of a rear portion of the bolt.

[0049] Other features of the gun 100 of FIG. 4 include a pneumatic circuit for driving the shooting mechanism (that is, the bolt and hammer combined) forwardly towards a front shooting position. This pneumatic circuit includes the aforementioned solenoid valve 152 which is arranged to receive gas under pressure from the regulator 160 and direct this gas to a rear side of the hammer 42 when the gun is shot. In order to conduct the pressurized gas from the outlet of the solenoid valve to the passageway 126 of the plug member 120, there extends through the grip 14 a flexible hose 190. The top end of this hose is connected to a hose connector 192 having a round extension 194 forming a passageway aligned with the end of the passageway 126. The bottom end of the hose connects to the upward extension 162 of the regulator which is formed with internal gas passages 196. It will be understood that the inlet of the solenoid valve is connected by means of a suitable one of these passageways to the outlet of the regulator. Shown in FIG. 13 is the top end of the upward extension 162. The inlet of the solenoid valve is connected to the outlet of the regulator 160 at opening 270 while the outlet of the valve is connected to an opening at 271. The bottom end of hose 190 is connected to the outlet opening at 272.

[0050] The gun 100 is also provided with a paintball shooting gas valve 76 similar to the corresponding gas valve in the first version of the gun and also mounted forwardly of the chamber containing the hammer 42. This gas valve has a downward extension 20 which can be seen in FIG. 4 and an external hose (not shown but similar to the hose 18 of FIG. 1) extends from the bottom of the extension 20 to a side outlet for high pressure gas located at 200. This side outlet can be formed in the side of the connector housing 12′ which is internally threaded at 16′ to receive a CO₂ cylinder. As in the first version of the gun, the gas valve 76 is adapted to be open by engagement by the hammer 42 in the front shooting position to permit passage of pressurized gas from a pressurized gas source (ie. the aforementioned CO₂ cylinder) to the barrel to propel the paintball. The gas valve 76 is mounted in the upper body section 104 and it has an inlet in the downward extension 20 connectible to the pressurized gas source. Again, this valve 76 receives relatively high pressure gas usually having a pressure of at least 600 psi or more and this valve has an outlet opening into the bolt chamber of the breech section. When the hammer engages a gas releasing pin 202 at the rear end of the valve, the valve 76 will be open for a brief period of time sufficient to shoot the paintball at an appropriate speed. The valve 76 can be considered part of a first pneumatic circuit in the gun for delivering propellant gas at a relatively high pressure to the barrel.

[0051] Also shown in FIG. 4 is the location of a standard DC battery 204 which in this gun is located in the lower body section above the trigger. In a preferred version of this gun, the battery is a 9 volt battery that is connected by its terminals to the circuit board 154 in a manner described in more detail below. The battery is the power source for the electronic circuit which in a preferred version will switch off automatically under predetermined conditions (such as a period of non-use) in order to save the life of the battery. It will also be understood that means (not shown) are provided for gaining access to the battery compartment in the handle, for example, a removable battery cover can be provided in the lower body section 106 on one side of the battery chamber.

[0052] In one preferred embodiment of the gun, the solenoid valve 12 is a standard valve operable on six volts, such as model EV-3M 6VDC available from Clippard, a U.S. company.

[0053] Reference will now be made to FIG. 12 which illustrates a preferred form of electronic circuit for controlling the pneumatic circuit which includes the aforementioned solenoid valve 152. In the illustrated circuit, the 9 volt battery 204 with its terminals is indicated on the right side and the solenoid valve 152 is indicated on the left side. The basic electronic circuit as illustrated includes two integrated circuits identified as U1 and U2 and four transistors. Preferably U1 is an eight bit microcomputer such as MCU Model PIC12C508/SO available from Microchip. This particular microcomputer has built-in internal R/C oscillation, an internal power up reset, and LED direct drive capability and is one time programmable. The voltage to the microcomputer U1 is controlled and regulated by voltage regulator U2 such as the regulator part No. UA78L05C/SO. This regulator is able to provide a positive 5 volts V_(CC) which powers the capacitors C1 and C2 and the microcomputer.

[0054] The voltage level provided is monitored by a brown out circuit indicated at 210. The purpose of this circuit is to reset the microcomputer and prevent its operation when the voltage being provided is below a certain level, for example, 4 volts. Once the voltage level across V_(BE) is less than 0.7 volts, the transistor Q4 will be switched off from the V_(CC) and the resistance of R₄ (which is one tenth of the internal pull up value on the master clear (MCLR) pin) will pull down the voltage level on the MCLR pin to a point that the microcomputer is put in a reset state. This brown out circuit is desirable due to the rapid On/Off of the power On/Off switch which may induce voltage fluctuation that could incorrectly reset the microcomputer U1.

[0055] Another significant aspect of the illustrated circuit is an electronic ON/OFF switch indicated at 212. The transistors Q1 and Q2 provide this electronic ON/OFF switch. Any bias current across Q1 BE junction will cause Q1 to conduct. The transistor Q2 acts as a latch to supply power to the electronic circuit once the microcomputer has been turned on and after the power ON/OFF switch is released. A suitable transistor for Q1 is MMBT 3906 while a suitable transistor for Q2 is MMBT 3904. The resistance R8 puts the transistor Q1 in reverse bias in the OFF state. The resistance R7 which is located between transistors Q1 and Q2 limits the bias current across Q1 and the collector current into Q2.

[0056] The circuit of FIG. 12 includes three mechanically operated or manually operated electrical switches SW1, SW2 and SW3. The switch SW1 is a manual power ON/OFF switch which can, for example, be located on a side of the gun handle 14. This switch permits the user of a gun to switch the circuit to the ON condition so that the gun can be operated. The switch SW2 is used for setting the firing sequence of the gun. In one preferred electronic circuit the firing sequences that are available are one shot, two shot, three shot, and five shots for each trigger pull or automatic fire. The user can select which firing sequence he wants by simply pushing the switch button or pin the number of times that he wants the gun to fire for each trigger pull. In other words, if the switch SW2 is pushed twice, the firing sequence will be two paintballs fired for each trigger pull. The selected firing sequence will be indicated by the flashing sequence of the light emitting diode (LED) D1. A fire-select routine of the program of the microcomputer causes the LED diode to flash in this manner and once the firing sequence is selected, this routine will wait until the selection key is released before it goes back to the main loop of the program. The switch SW3 is the switch operated by the trigger 54. A suitable switch for SW1 and SW2 is switch part TS-1143 while a suitable switch for SW3 is switch part TS-1131V.

[0057] It will be understood that the transistor Q3 is a current booster that drives the solenoid valve at 152 with the diode D5 acting to protect the back EMF from the solenoid valve. The diode D6 located in a line between the battery and the electronic ON/OFF switch is a polarity protector to protect the circuit should the 9 volt battery 204 be installed in wrong polarity. The item 214 indicated in the upper right corner of the circuit near the diode D6 represents an optional additional ON/OFF switch that can be manually operated. If this optional switch is not provided, then the terminals for this switch are shorted. Also, the various small square boxes shown in FIG. 12 and indicated by references 216 to 223 are simply test point locations used by the manufacturer of the electronic circuit.

[0058] Once the transistor Q2 is conducting, it grounds the signal path on GPO, GP1 of the microcomputer U1 to inform the computer that the electronic circuit will be switched OFF. The diodes D2 and D3 are used to avoid cross-conduction between GPO and GP1 while the diode D4 is used to block current flow in the reverse direction, along conduction path 230 that extends between the switch SW1 and the electronic switch 212. The resistor R13 located between Q4 and the microcomputer is used to isolate the brown out circuit for In-circuit programming, that is, programming the one time programmable circuit board.

[0059] In one preferred, programmed electronic circuit for the gun of this invention, the ON time for the solenoid valve is fixed at 15 mS and 17 mS for shots after the first, thus allowing more gas flow for repeating shots. The maximum shots per second are limited to eight shots per second in the preferred program in order to give sufficient loading time for each paintball to drop into the gun breech under natural gravitational force.

[0060] Set out below is a list of the resistors used in the preferred circuit of FIG. 12 along with resistance values in a particular preferred version of this circuit: RESISTORS SIZE R1 68K R2 330K  R3 33K R4 4K7 R5 150 R6 33K R7 4K7 R8 4K7 R9 33K R10 33K R11 470 R12 4K7 R13 470

[0061] With respect to the diodes used in a preferred version of the circuit of FIG. 12, the diodes that can be used are as follows: DIODES IDENTIFIED D1 LED D2 LL4148 D3 LL4148 D4 LL4148 D5 DL4001 D6 DL4001

[0062] All of the diodes have a threshold value of 0.7V.

[0063] With respect to the capacitors used in this preferred circuit, the capacitance values are as follows: C1 100 nF C2 22 uF

[0064] The microcomputer U1 is programmed in the following manner. After the power is reset, the microcomputer U1 initializes the I/O direction register. The I/O ports are set which latches the electronic ON/OFF switch 212 into the “ON” state. The RAM is cleared and the following parameters are set:

[0065] 1) Set the ON time for the solenoid valve 152.

[0066] 2) Set the period to fire a single shot.

[0067] 3) Initialize the time interval to run the routines.

[0068] 4) Initialize the default number of fires per trigger pull (default=single shot per trigger pull).

[0069] 5) Turn on the LED.

[0070] The program will wait until the power ON/OFF switch is released by the user and then the program will loop around the main loop routine to check if any key has been pressed, for example, the selection switch or the trigger switch. If the trigger has been pressed, it will go to a routine to turn on the solenoid and loop around to complete the number of shots that have been selected. Then it will wait until the trigger is released before it returns to the main loop routine.

[0071] If the switch for the shot selection has been pressed, it will go to a firing routine to change the number of shots fired per trigger pull. In a preferred embodiment, the possibilities that can be selected include one shot, two shot, three shot or five shots per trigger pull, or automatic firing. Once selected, it will change the flashing sequence of the LED to indicate the new setting and wait until the selection key is released before it goes back to the main loop routine. If the program detects that both the trigger switch and the selection switch have been pressed simultaneously, it will assume that this is a power OFF signal and turn the LED OFF. The program then waits until the switch or switches are released and turns off the latch on transistor Q1 and goes into a dead loop until the power is cut.

[0072] Note that in any program loop in the main program, a timer routine will be called upon. This is a timer service routine served every 1 mS. It is the timer routine in the microcomputer which enables the microcomputer to turn the solenoid value to the ON position for the required time intervals, for example, 15 mS or 17 mS.

[0073] The gun 100 can be provided with any suitable form of known safety mechanism to prevent the gun from accidentally being fired. The illustrated gun 100 is provided with a known type of safety mechanism, this mechanism including a safety spring 250 and a safety pin 251. In a known manner the spring 250 biases upwardly a small ball bearing located at the top thereof. This bearing can engage one of two small, annular grooves extending about one end section of the pin 250 in order to hold it in the desired position. The horizontal pin 250 has a central groove or recess that, when aligned with the horizontal extension of the trigger, will allow the trigger to be pulled and the gun shot. Also shown in FIG. 4 is a small spring at 252 to bias the trigger away from the firing position.

[0074] It will be appreciated that various modifications and changes can be made to the paintball guns as described herein without departing from the spirit and scope of this invention. Accordingly, all such modifications and changes as fall within the scope of the appended claims are intended to be part of this invention. 

What is claimed is:
 1. A paintball gun operable to shoot paintballs, said gun comprising: a barrel; a gun body section including a breech section connected to a rear end of said barrel and a handle section; a trigger movably mounted on said gun body section; a bolt movable in said breech section between a retracted position where a paintball can enter said breech section through an inlet provided in said breech section and a front shooting position where said inlet is closed; a hammer connected to said bolt and movable therewith, said hammer being slidable in a sealable chamber in said gun body section between a rearward position and its front shooting position, said bolt and said hammer together forming a paintball shooting mechanism; a spring mounted in said gun and engaging said paintball shooting mechanism, said spring biasing the hammer towards said rearward position; a pneumatic circuit for driving said shooting mechanism forwardly towards said front shooting position and including a control valve arranged to receive gas under pressure and direct this gas to a rear side of said hammer when said gun is shot; an electronic circuit for controlling said pneumatic circuit, said electronic circuit including an electrical switch operated by movement of said trigger; and a gas valve mounted in said gun and adapted to be opened by engagement by said hammer in said front shooting position to permit passage of pressurized gas from a pressurized gas source to the barrel to propel a paintball along and out of said barrel.
 2. A paintball gun according to claim 1 wherein said spring is a coil spring mounted in said breech section and engaging said bolt.
 3. A paintball gun according to claim 1 including a battery connected to said electronic circuit and capable of powering said electronic circuit, which includes a manual ON/OFF switch.
 4. A paintball gun according to claim 3 wherein said electronic current includes a microcomputer and means for regulating a predetermined voltage from said battery that is provided to said microcomputer.
 5. A paintball gun according to claim 1 wherein said spring is a coil spring mounted in said gun body section and engages said hammer directly.
 6. A paintball gun according to claim 1 wherein said electronic circuit includes a timer capable of controlling the length of time said control valve directs gas under pressure into said sealable chamber when said gun is shot.
 7. A paintball gun according to claim 4 wherein said microcomputer includes an electronic timer to control the length of time said control valve directs gas under pressure into said sealable chamber when said gun is shot.
 8. A paintball gun according to claim 1 wherein said electronic circuit includes a microcomputer, a voltage regulator to control the voltage of current provided to said microcomputer, a brown out circuit connected to said microcomputer, an electronic switch capable of switching said electronic circuit off under preselected conditions, and a manual ON/OFF switch.
 9. A paintball gun according to claim 8 wherein said microcomputer has built-in R/C oscillation, internal power-up reset, and LED direct driving capability and is connected to a LED diode, and wherein a visual indication of a current operational state of the electronic circuit can be provided by said microcomputer by lighting of said LED diode.
 10. A paintball gun according to claim 6 wherein said control valve is a solenoid valve having an outlet connected by a pressurized gas passageway to a gas outlet in said gun body section located at said rear side of said hammer.
 11. A paintball gun according to claim 1 wherein said hammer is rigidly connected to said bolt by a metal pin that extends through an elongate slot formed in said breech section below the bolt.
 12. A paintball gun according to claim 1 wherein said gas valve is mounted in said gun body section in front of said hammer and has an inlet adapted for connection to said pressurized gas source, said gas valve being adapted to receive relatively high pressure gas having a pressure of at least 600 psi, said gas valve having an outlet opening into a bolt chamber of said breech section.
 13. In a gas-powered gun for filing balls, the gun having a barrel, a gun body section including a breech behind the barrel for receiving one ball at a time through a ball feed port, a trigger movably mounted in said gun body section, a bolt slidable within the breech to advance a ball to a shooting position and close off the feed port, and a regulator for supplying pressurized gas at a relatively low gas pressure, said regulator being adapted for connection to a source of relatively high pressure gas, the improvement comprising: a hammer rigidly connected to said bolt and movable therewith, said hammer being slidable in a sealable chamber formed in said gun body section between a rearward position and a front shooting position, said bolt and hammer together forming a ball shooting mechanism; means for biasing said shooting mechanism so as to move said hammer towards the rearward position; a solenoid valve having an inlet connected to said regulator and arranged to deliver said relatively low pressure gas to a rear side of said hammer for moving said ball shooting mechanism forwardly to the shooting position when said solenoid valve is in an open position; an electronic circuit for controlling said solenoid valve, said circuit including an electrical switch operated by said trigger; and valve means for permitting said relatively high pressure gas to flow into said barrel in order to propel a ball along and out of said barrel, said valve means being moved to an open position by engagement of said hammer in said front shooting position.
 14. A gun according to claim 13 wherein said biasing means is a coil spring mounted in said breech and engaging said bolt at one end of the spring.
 15. A gun according to claim 13 including a battery connected to said electronic circuit in order to power same, wherein said electronic circuit includes a manual ON/OFF switch and an electronic switch which is capable of shutting down said electronic circuit automatically in order to save battery power.
 16. A gun according to claim 15 wherein said electronic circuit includes a microcomputer and a voltage regulator for controlling voltage level of current provided to said microcomputer.
 17. A gun according to claim 16 wherein said electronic circuit includes a manually operated switch for programming said microcomputer to cause said gun to shoot a selected number of balls with each pull of said trigger, one ball being fired by said gun each time said solenoid valve is moved to said open position by said microcomputer.
 18. A paintball gun operable to fire paintballs, said gun comprising: a barrel; a gun body section attached to said barrel and including a breech section coaxial with said barrel and a movable trigger, a bolt mounted in said breech section and movable between a retracted position for paintball loading and a forward position for shooting a paintball; a hammer rigidly connected to said bolt and movable therewith, said hammer being slidable in a sealable chamber in said gun body section between a retracted position and a forward position; spring means for moving the combination of said bolt and said hammer to said retracted position after a paintball is shot; a first pneumatic circuit for delivering propellant gas at a relatively high pressure from a gas supply to said barrel for propelling said paintball therefrom, said first pneumatic circuit including a relatively high pressure gas valve; a second pneumatic circuit connected to receive pressurized gas from said gas supply and including a solenoid valve for delivering relatively low pressure gas to a rear end of said hammer for a short time interval in order to drive the combination of the hammer and the bolt from said retracted positions to their respective forward positions and thereby causing said hammer to strike said gas valve to open it and release said propellant gas to the barrel; and an electronic circuit adapted to operate said solenoid valve, said electronic circuit being operable by said trigger.
 19. A paintball gun according to claim 18 wherein said spring means is a coil spring mounted in said breech section and engaging said bolt at one end of the coil spring.
 20. A paintball gun according to claim 18 wherein said second pneumatic circuit includes a single regulator for supplying said relatively low pressure gas to an inlet of said solenoid valve. 